Process and apparatus for producing sheets of glass



J, L. DRAKE 1,842,51' PROCESS ANDMPPARATUS FOR PRODUCING SHEETS 0F GLASS Jan. 26, 1932..

Filed Jan. 13. 1928 2 Sheets-Sheet l -..NTU

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PROCESS AND APPARATUS FOR PRODUCING SHEETS OF GLASS 2 sheetssheet 2 Filed Jan. 13, 1928 llmtatented dans Qd, 193i@ PATENT OFFICE il" l. BRAKE, 01E TLIEDQJEIW, ASSIGNOR 1Y0 IBBEY-WENS-FORD GLASS COMPANY, F TILElDO, OHIO, A UURPORATION OF GHI() PBCESS AND APPARATUS FUR PRODUCING SHEETS 0F GLASS lApplication filed January 13, 1928. Serial No. 246,415.

u tion is to provide a process and apparatus whereby relatively thin sheets of glass may he formed employing sheet forming m-echanism in which the sheet is rolled to final thickness upon a reciprocable member.

:i A Another object of this invention is to provide a process and apparatus of this nature wherein the formed sheet is removed from contact with the reciprooable table substantially immediately after being reduced to final sheet form wherein excessive cooling of the sheet is prevented and the corresponding disadvantages incident to such cooling1 eliminated.

Another object of the invention is to pro- I vide a process and apparatus of the herein described character wherein the stripping means is stationary or fixed with reference to the reciprocable table of the sheet forming means whereby the stripper cooperates there- :su with and acts to strip the sheet therefrom during the movement of the table in one direction in the sheet forming operation.

ilinother object of the invention is to provide a process and apparatus of the character described wherein a temperature controlled Hattening chamber is employed into which the sheet is introduced as it leaves the sheet forming means.

@till another object of the invention is to ll provide such a process and apparatus Wherein the sheet stripping means also directs the sheet into the flattening chamber.

it. further object is to provide such a process and apparatus wherein the flattening chamlJ ber is provided with sheet supporting rolls for receiving and supporting the sheet While passing through this chamber and further for delivering the sheet therefrom to a lehr.

r-lnother object is to provide such a process and apparatus wherein the sheet is maintained in proper longitudinal tension during its passage through the flattening chamber as for instance by providing means for driving the sheet supporting rolls located therein at a speed substantially coincident with the speed of travel of the reciprocable table or at a speed slightly in excess thereof.

Various other objects and advantages and also novel details of construction of the apparatus forming part of the subject matter of this invention will be made more apparent as this description proceeds, especially when considered in connection with the accompanying drawings, wherein:

Figure 1 is a fragmentary vertical longitudinal sectional view through a sheet forming apparatus constructed in accordance with this invention.

Figure 2 is a fragmentary view partly in top plan View and partly in horizontal section of the structure illustrated in Figure 1.

Figure 3 is a vertical transverse sectional view taken substantially on the plane indicated by line 8-3 in Figure 1..

Figure 4 is a vertical longitudinal sectional view through a modified form of sheet forming apparatus constructed in accordance with this invention, and

Figure 5 is a view showing the construction of the variouspairs of rollers employed in the apparatus shown in Figure 4.

Referring now to the drawings and more especially to Figures l to 3 thereof it will be noted that there is illustrated a sheet forming mechanism including a reciprocable member or a table 10 movable along a track or guideway 11 by means of Wheels or the like 12. While the table 10 may be reciprocated in any desired manner the driving means herein illustrated consists of a gear 13 mounted on a shaft 14C and meshing with a rack 15 secured to the table 10.

Mounted above the table 10 and in spaced relation thereto is a roll 16, this roll being rotatably mounted by means of a shaft 17 journaled in fixed brackets 18. While the roll 16 is fixed with reference to the path of travel of table 10 it may, if desired, be adjustably mounted so as to vary the distance between the surface of this roll and the surface of the` top of the table 10. The roll 16l may, also, if desired, be positively rotated in timed relation to the movement of table 10 by means of gears 16 fixed for rotation with the roll 16 and adapted to'mesh with racks 17 carried by the table 10.

The roll 16 and table 10 cooperate to provide a sheet forming pass 19. The temperature of the roll 16 may be controlled, in the customary manner, by passing a cooling or heating medium throu h the passageway 2() formed through shaft 1g?.

The upper surface of the table 10 may, if desired, and preferably is, provided with thickness maintaining ledges 21 ,extending longitudinally thereof adjacent the longitudinal edges. Ordinarily the roll 16 is so adjusted as to be brought into engagement with the upper face of these-ledges 21. rLhese ledges also prevent the spreading of the `molten glass during the sheet forming operation beyond the limits defined thereby.

In manufacturing sheet glass with sheet forming apparatus similar or generally similar to that herein illustrated and just described it has heretofore been necessary to produce a sheet materially thicker than the sheet capable of being successfully produced in accordance with this invention. It has lalso been necessary to permit the sheet to remain upon the forming or casting table a suiiicient length of time to allow the same to become partly cooled and set. The production of a thicker sheet and the partial cooling and setting ofthe sheet have been found necessary in order to acquire sucient rigidity in the sheet to permit the same to be pushed off the casting table.

However, in accordance with the present invention I propose a process and apparatus wherein relatively thinner sheets may be produced and substantially immediately stripped from the casting or forming table and introduced into a temperature controlled flattening chamber. In addition to being able to produce much thinner sheets the nished sheet is permitted to remain in contact with the casting or forming table only a very short time thereby reducing the cooling e fect of the table upon the sheet and eliminating the possibility of the sheet cracking by lreason of such cooling. To this end there is provided a stripperor stripping means 22 extending transversely of'the table 1() and fixedly supported slightly above the upper surface thereof. -The stripper herein illustrated is provided with a lower surface 23 parallel with the upper surface of table 10 and with an upper surface 24 inclined upwardly in the direction of movement of the table 10. The stripper may be made hollow and a temperature controlling medium circulated therethrough by means of pipes 25. The stripper, it is understood, is iixedly, although adjustably, mounted and adapted to cooperate with the table 10 to strip the sheet therefrom as the table moves thereunder, the stripper being initially located adjacent the forward end of the table 10.

The reference character 26 indicates generally a chamber constituting a flattening chamber into which the'sheet of glass is introduced immediatel after it is stripped from the forming ta le 10. Thetemperature of this flattening chamber may be suitably controlled b.y means of burners 27 and located in the chamber is a plurality of sheetv supporting rolls 28. The temperature of these rolls may also be regulated by passing a temperature controlling medium through the hollow interiors 29 thereof.-

The rolls 28 are revolvably mounted and may be driven at a speed coincident with the travel of the table 10 or at a speedslightly in excess thereof to thus maintain the sheet in proper longitudinal tension. As one means of rotating the rolls 28 there is illustrated sprocket wheels 30 carried upon the shafts of the rolls 28 at one end thereof and a sprocket chain 31 engaging these sprocket wheels.

From the examination of Figure 1 it will be noted that during the reciprocation of the table 10 toward the right this table passes under the stripper 22 and into the flattening chamber 26, and also under the sheet supporting rolls 28.

Located adjacent the outlet end of the attening chamber 26 is a lehr 32 of any preferred or desired construction, the sheet passing from the rolls 28 of the iattening chamber onto the sheet supporting rolls 33 located in the lehr.

The present invention preferably contemplates the formation of the glass sheets from a mass of molten glass 34 which has previously been completely melted and refined in -receptacles or pots such as receptacle 35. Under such conditions batch glass ingredients are introduced into each of said receptacles, which receptacles are then subjected to high temperatures to produce molten glass and after the glass batch has been melted the temperatures are controlled to permit perfect reining and settling of the glass. The completely melted and refined molten glass is then introduced to the sheet forming means previously described by depositing the same upon the forming table 10 adjacent the forming roll 16 and sheet forming pass 19.

In Figures 4 and 5 a modified form of oo nstruction has been illustrated, this form of construction differing from the previously described form principally in the character and construction of the sheet forming mechanism. In consequence of the general similarity between the. two forms of apparatus only those features of the apparatus which differ from those previously referred to will be described in detail.

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retratar ilhe sheet forming means consists essentially of a plurality of pairs or sets of forming rolls 36, 37 and 38 arranged in substantially vertical alignment with one another with the rolls of cach pair being spaced apart to permit the glass to pass downwardly therebetween. rllhe several pairs of rolls are off respectively increasing lengths from the uppermost rolls 36 to the lowermost rolls 38. lhe rolls 36 and 37 gradually taper from their centers toward their opposite ends while the lowermost rolls 38 are truly cylindrical to form a straight sheet forming pass therebetween having parallel sides. rlhe degree of A taper of' the several sets of rolls gradually decreases from the uppermost pair so that in effect the rolls gradually approach cylindrical form. @ue to the particular construction of the forming rolls, the space between the rolls of each succeeding pair is less than the space between the rolls of the preceding pair so that the stream of molten glass passingI downwardly between the pairs of rolls is gradually reduced in thickness. Furthermore, because of the formation of the rolls, the glass is spread outwardly from the center towards the opposite ends thereof and thus, the stream while being gradually reduced in thiclness is simultaneously increased in width so that the resulting sheet will be of substantially predetermined dimensions.. @ne of the lowermost pair of rolls 38 cooperates with the table l to reduce the sheet to final thiclmess and in this manner acts and functions substantially similar to roll 16 of the reviously described form of construction.

l e pairs of rolls 36, 37, and 38 are arranged in a chamber 39, the temperature of which may be controlled by means of burners lll), this chamber being provided with an opening Zll adjacent the upper end thereof whereby the molten glass from receptacle may be deposited upon the uppermost pair of rolls 36.

lWhile two forms of sheet forming means have been illustrated and described herein it will be readily apparent that various other types and constructions of sheet forming means may be employed with equal facility. However, it will be noted that in each of the herein described forms of construction stripping means is provided which acts to strip the sheet from oneofthe elements of the sheet forming means and to direct the same into the flattening chamber. Thus as previously mentioned thinner sheets may be produced than have heretofore been possible with sheet forming means of this general cha-racter and the sheet readily transferred nevertheless to the flattening chamber. Furthermore as also previously mentioned the sheet is permitted to remain in engagement with the forming or casting table but momentarily so that the possibility of the formation of cooling cracks is eliminated.

While several'forms of the invention have been illustrated and described herein somewhat in detail and a certain sequence of the steps of the process recited, nevertheless it will be obvious to those skilled in this art that various changes, modifications and rearrangements of the herein described details may be resorted to without departing from the spirit and scope of this invention and to this end reservation is made to make such changes asmay come withinl the purview of the accompanying claims.

ll claim:

l. ln sheet glass apparatus, a reciprocable table, a rotatable member associated therewith in a manner to create a sheet forming pass, said table being movable beneath` the rotatable member, a stationary sheet stripper member placed above the table and having a portion substantially in contact therewith, one end of the stripper member terminating in close proximity to the sheet forming pass, a conveyor extending horizontally from the stripper member and having its upper supporting surface substantially in horizontal alignment with the uppermost part of the stripper member, the conveyor also being arranged in a plane above the upper surface of said table so that the table can move thereunder without interference therewith, and means for depositing a mass of molten glass uponthe reciprocable table in advance of the sheet forming pass whereby, upon movement of the table in one direction, the glass will be reduced to sheet form, stripped from the table, and directed to said conveyor.

2. ln sheet glass apparatus, a reciprocable table, a rotatable member associated therewith in a manner to create a sheet forming pass, said table being movable beneath the rotatable member, a stationar sheet stripper member placed above the tab e and having a portion substantially in contact therewith, one end of the stripper member terminating in close proximity to the sheet forming pass, a conveyor extending horizontally from the stripper member and having its upper supporting surface substantially in horizontal alignment with the uppermost part of the stripper member, the conveyor also being arranged in a plane above the upper surface of said table so that the table can move thereunder without interference therewith, means for depositing a mass of molten glass upon the reciprocable tablein advance of the sheet forming pass whereby, upon movement of the table in one direction, the glass will be reduced to sheet form, stripped from the table, and directed to said conveyor, and means for effecting flattening of the sheet while on said conveyor.

3. In sheet glass apparatus, a reciprocabletable, a rotatable member associated therewith to create a sheet forming pass,said table being movable beneath said rotatable mem- SUI ber, a stationary sheet stripping member mounted above the table and having a portion thereof terminating substantially beneath the rotatable member, means for depositing a mass of molten glass upon the reciprocable table in advance of the sheet forming p ass, means for moving the table Whereby the glass will be reduced to sheet form, with the sheet being permanently removed from the table by the stripping member sub stantially immediately after its formation and before the entire sheet has been formed, a temperature controlled compartment, and conveying means located Within the com artment for receiving the sheet thereupon rom the stripping member, said conveying means being positioned above the levelof the table so that during removal of the sheet there-` from, the said table can pass beneath the conveying means.

Signed `at Toledo, in the county of Lucas and State of Ohio, this 11th day of January,

' JOHN L. DRAKE. 

